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Ok, I just got this problem. I figure I ask and so far searching here doesn't have the same exact situation.

Both my cooling fans are running even with the keys not in the ignition. Car starts up fine and even the AC works fine but every time I have to pull the battery off just so it doesn't kill the battery.

What I have done is replaced the AC Coolant Sensor. It was a pain to remove being on the side of the engine and difficult to release and plug back but I was able to do it.

Yet the fan still immediately runs once there is power.

Would this be a fan control module problem or relay in the fuse box?
 

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Engine cooling fans often have more than one sensor and controllers can be linked to others. You need to have a diagnostics scan done to help you find the problem. The fan cooling control system is designed to be failsafe. If something is wrong, the fans will be put on continuously to protect the engine. I'm not sure if they use a relay or if its solid state in the controller. Fans usually have an 'always on' power feed to cool the engine bay at ignition off.
 

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Engine cooling fans often have more than one sensor and controllers can be linked to others. You need to have a diagnostics scan done to help you find the problem. The fan cooling control system is designed to be failsafe. If something is wrong, the fans will be put on continuously to protect the engine. I'm not sure if they use a relay or if its solid state in the controller. Fans usually have an 'always on' power feed to cool the engine bay at ignition off.
I think I need a proper VW scanner. I connected a general OBD scanner tool and I am able to read the coolant temp at 33C with the ignition On but engine off but the fans continue to spin nonstop so I'm gonna check the relays if they are Open or not.
 

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Good Luck finding relays. They use electronic power control using mosfets with input from the ECU. Temperature is data transmission via CANbus not just sensors and direct connections you might think. Some of these have fan d.c speed control, which is why you need V.W specific diagnostic tools or have it scanned by somebody who knows how to do it properly and understand the results.

Fan 1 has the intelligent controller built in to the fan assembly which also feeds Fan 2 so they could if needed, put each fan on independently.
 
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